Pilot plant studies on fixed bed reactor system for biomethanation of distillery spent wash

Abstract

High strength distillery spent wash was successfully treated in fixed film fixed bed two‐staged anaerobic reactors using cheaper and abundantly available pebbles as media on laboratory scale. Encouraged with the results, further studies were carried out on pilot scale for the same reactor system installed in an Indian distillery.

Optimum loading were observed as 10 Kg COD/m³.d (reactor‐I) and 3 Kg COD/m³ .day (reactor‐II) with detention period of 2.43 days with an influent COD concentration of approximately 50,000 mg/L. The overall COD removal was about 80% with a specific biogas yield of 0.30 m³CH₄/Kg COD_r.

This paper deals with the detailed performance evaluation of the reactor system on pilot scale for biomethanation of distillery spent wash and determination of the relevant kinetic constants based on various models.

Key words:

• Biomethanation
• fixed bed reactor
• spent wash
• optimum loading
• kinetic constants